During plasma processing of semiconductor substrates wherein the semiconductor substrates are exposed to halogen-containing process gases, a residue of the process gases, e.g. a residue containing bromine, can remain on surfaces of the semiconductor substrates. Such residue can cause defects in the semiconductor substrates in downstream processing steps, and can contaminate other semiconductor substrates in the processing pipeline. Therefore, it is desirable to remove such residue from the semiconductor substrates in a degas chamber.